EP3036276A1

EP3036276A1 - Method for producing a composite plastic part (ck)

Info

Publication number: EP3036276A1
Application number: EP14752861.6A
Authority: EP
Inventors: Gijsbrecht HABRAKEN; Manoranjan Prusty; Andreas Radtke; Gaurav Ramanlal KASALIWAL
Original assignee: BASF SE
Current assignee: BASF SE
Priority date: 2013-08-21
Filing date: 2014-08-18
Publication date: 2016-06-29
Anticipated expiration: 2034-08-18
Also published as: PL3036276T3; CN105658705B; KR102318323B1; JP6169281B2; ES2655563T3; KR20160045834A; EP3036276B1; CN105658705A; US20160207238A1; WO2015024913A1; JP2016528081A; US10583595B2

Abstract

The invention relates to a method for producing a composite plastic part (CK). A first fiber material (F1) is impregnated with a polyamide matrix polymer (PAM), thereby obtaining a matrix composition (MZ), onto which a surface composition (OZ) is applied, and a first plastic component (K1) is obtained. In a second step, a second plastic component (K2) is molded on the first plastic component (K1), whereby the composite plastic part (CK) is obtained. The invention further relates to the composite plastic part (CK) which can be obtained using the method according to the invention. The invention additionally relates to the use of polyethyleneimine (PEI) for improving the impregnation of the first fiber material (F1) with the polyamide matrix polymer (PAM).

Description

The present invention relates to a method for producing a composite plastic part (CK), in which a first fiber material (F1) is impregnated with a polyamide matrix polymer (PAM) to obtain a matrix composition (MZ), to which a Surface composition (OZ) is applied, and a first plastic component (K1) is obtained. In a second step, a second plastic component (K2) is formed on the first plastic component (K1), whereby the composite plastic part (CK) is obtained. Moreover, the invention relates to the composite plastic part (CK) obtainable by the process according to the invention. Another object of the present invention is the use of polyethyleneimine (PEI) to improve the impregnation of the first fiber material (F1) with the polyamide matrix polymer (PAM).

Fiber-reinforced plastics have been established as materials for many years, which are used in many applications as a replacement for metal parts. Fiber-reinforced sheet-like plastics are therefore also referred to as organic sheets. The use of fiber-reinforced plastics is intended to reduce the weight of the materials used and the manufacturing costs of the materials. In fiber-reinforced plastic parts, usually a glass, carbon or aramid fiber in the form of a fabric or a fabric is enclosed by a polymer. The fiber-reinforced plastic parts thus obtained can be produced inexpensively, are lightweight compared to comparable metal parts and are characterized by good mechanical properties.

Thermosetting polymers were used as polymer components for the first fiber-reinforced plastic parts. In order to achieve greater design freedom in terms of processing and further processing, as well as the forms that can be produced with fiber-reinforced plastics, fiber-reinforced plastics containing thermoplastics as a polymer component have been developed.

In order to further increase the freedom of design and the design options, fiber-reinforced plastics can be further processed by welding and encapsulation. The welding and encapsulation of endless fiber reinforced plastic sheet-like parts is described for example in Marco Wacker et al., "Welding and encapsulation of organo sheets", KU plastics, Karl Hanser Verlag Munich, born 92 (2002), 6 Behind or overmolding functional elements can be attached to the fiber reinforced plastic sheet parts fiber-reinforced sheet-like plastic preheated prior to insertion into the mold and then encapsulated with a second polymer.

In order to achieve a good connection between the first plastic part and the second polymer injected into the mold, it is necessary, as described above, to preheat the first plastic element. For preheating, for example, infrared radiators or ovens can be used. By preheating the first plastic element is softened and optionally fused to the surface. The heating can be done outside of the mold. It is also possible to carry out the heating directly in the mold. As a result, deformations of the softened first plastic element can be avoided.

In order to achieve a sufficiently high strength of the connection (adhesion) between the first plastic element and the second plastic element, a sufficiently deep melting of the surface of the first plastic element is necessary, so that a stable welded joint is formed. Due to the preferred heating of the first plastic element in the mold, a high cycle time is required until the finished molded part can be removed from the mold, since a removal is usually only possible if the polymer of the first plastic element and the polymers as a component of the second plastic element are injected into the molded part, as far as solidified that the molded part is dimensionally stable. For this purpose, the mold is usually cooled prior to removal of the finished molded part.

In order to achieve a sufficient adhesion between the first and the second plastic element and thus a good stability of the resulting composite plastic part (CK), various methods have been described in the prior art.

US 2008/0176090 A1 describes a composite plastic part which contains a first and a second plastic component. To improve the adhesion, a so-called adhesion promoter layer is used between the first and the second plastic component. The adhesion promoter layer contains ethylene vinyl alcohol copolymers, ethylene vinyl acetate copolymers or ionomers, such as, for example, ethylene-based polymers which have carboxyl groups and in which the carboxyl groups are neutralized with metal ions. The composite plastic parts described in US 2008/0176090 already have good adhesion, but their preparation is complicated due to the need for an additional adhesion promoter layer. US 2012/0027983 describes polyamide composite plastic parts in which the use of a separate adhesion promoter layer is not absolutely necessary. The composite plastic parts also have a first and a second plastic component, wherein at least one of the plastic components contains 1 to 15 wt .-% of a functionalized polyolefin to improve the adhesion between the first and the second plastic component. As functionalized polyolefins, for example, polyolefins are used which are grafted with maleic anhydride. In composite plastic parts, a fiber-reinforced plastic element is often used as the first plastic element. For this purpose, for example, a fiber mat is impregnated with a plastic. For impregnation, the plastic is melted to enclose the fiber mat as completely as possible. In order to achieve good stability of the composite plastic part, it is necessary in this case for the fiber mat to be completely penetrated by the plastic. The individual fibers of the fiber mat should be as completely encased by the molten plastic. For this purpose, in the process described in the prior art, the plastic must be heated to high temperatures so that the plastic melt achieves a sufficiently low viscosity to ensure complete encasing of the fiber mat.

A complete sheathing of the fiber mat with plastic is necessary to ensure a good stability of the composite plastic part, after the second plastic element has been formed.

The high temperatures described in the prior art for impregnating the fiber mat are disadvantageous because the plastic melt is subjected to a high thermal load due to the high temperatures. This can lead to the degradation of the polymer chains in the plastic melt. In addition, complete sheathing of the individual fibers of the fiber mat is not always ensured in the methods described in the prior art.

The present invention is therefore based on the object to provide a method for producing a composite plastic part, which ensures the complete sheathing of the fiber materials used safely. In addition, the method is intended to ensure a sheathing of the individual fibers of the fiber materials, even at lower temperatures. In addition, the composite plastic part should have an improved or at least equivalent adhesion between the two plastic elements. The composite plastic part should also be stable against thermal loads. The composite plastic part obtainable by the process should have improved or at least equivalent heat aging resistance (WAB). The procedure should be easy and inexpensive to carry out. The composite plastic part obtainable by the method should have good mechanical properties. In particular, a good adhesion between the first and the second plastic component as well as an improved heat aging resistance (WAB).

The object is achieved by a method for producing a composite plastic part (CK) comprising the following steps: a) producing a first plastic component (K1) comprising the following steps: ia) impregnating a first fiber material (F1) with a polyamide matrix polymer (PAM) to obtain a matrix composition (MZ) and ib) applying a surface composition (OZ) containing a polyamide surface polymer (PAO) to the matrix composition (MZ) to obtain the first plastic component (K1), the surface composition (OZ) comprising a surface of the first plastic component (MZ) K1), b) molding a second plastic component (K2) containing a polyamide-forming polymer (PAA) to the surface of (K1), the matrix composition (MZ) containing a polyethylenimine (PEI).

It has surprisingly been found that with the method according to the invention a complete sheathing of the first fiber material (F1) is ensured by impregnation safe. The impregnation can be carried out according to the inventive method at lower temperatures. The composite plastic part (CK) produced by the method according to the invention has an improved adhesion between the first plastic component (K1) and the second plastic component (K2). The composite plastic part (CK) obtainable by the process according to the invention thus has good mechanical properties, in particular a very good adhesion between the first plastic component (K1) and the second plastic component (K2). The composite plastic parts (CK) can be produced more cost-effectively by the process according to the invention, since lower temperatures have to be used for the production. In addition, the composite plastic part (CK) obtainable by the process according to the invention exhibits improved heat aging stability (WAB) Compared to composite plastic parts made by the methods described in the prior art.

The following statements and preferences with regard to the method for producing a composite plastic part (CK) apply to the composite plastic part (CK) and the use of polyethyleneimine (PEI) to improve the impregnation of the first fiber material (F1) in the production of a composite plastic part (CK) corresponding. First plastic component (KD

The first plastic component (K1) is also abbreviated to K1 below. The matrix composition (MZ) is also abbreviated to MZ below. The polyamide matrix polymer (PAM) is also referred to below as PAM. The first fiber material (F1) is also abbreviated to F1 below. The surface composition (OZ) is also abbreviated to OZ below. The polyamide surface polymer (PAO) is also referred to below as PAO. Matrix composition (MZ)

The matrix composition (MZ) contains a polyamide matrix polymer (PAM) and at least one first fiber material (F1) for reinforcement. In the present case, the term "a polyamide matrix polymer (PAM)" is understood to mean both exactly one polyamide matrix polymer (PAM) and mixtures of two or more polyamide matrix polymers (PAM) .The same applies to the term "at least one first fiber material (F1)". This is understood according to the invention to mean both a first fiber material (F1) and mixtures of two or more fiber materials (F1).

Polyamide matrix polymer (PAM)

As stated above, exactly one polyamide matrix polymer (PAM) can be used as the polyamide matrix polymer (PAM). It is also possible to use blends of two or more polyamide matrix polymers (PAMs). Suitable polyamide matrix polymers (PAM) generally have a viscosity number of from 90 to 350, preferably from 10 to 240 ml / g. The determination of the viscosity number is carried out from a 0.5 wt .-% solution of the polyamide matrix polymer (PAM) in 96 wt .-% sulfuric acid at 25 ° C according to ISO 307th

As polyamide matrix polymers (PAM), semicrystalline or amorphous polyamides are preferred. Suitable polyamide matrix polymers (PAM) have a weight average Molecular weight (M _w ) in the range of 500 to 2 000 000 g / mol. The average molecular weight (M _w ) is determined by means of light scattering according to AMST D4001.

As polyamide matrix polymers (PAM), for example, polyamides are suitable which are derived from lactams having 7 to 13 ring members. As the polyamide matrix polymer (PAM), polyamides obtained by reacting dicarboxylic acids with diamines are further suitable.

Examples of polyamides derived from lactams include polyamides derived from polycaprolactam, polycapryl lactam and / or polylaurolactam.

In the event that polyamides are used which are obtainable from dicarboxylic acids and diamines, the dicarboxylic acid alkanes which can be used are dicarboxylic acids having 6 to 36 carbon atoms, preferably 6 to 12 carbon atoms. In addition, aromatic dicarboxylic acids are suitable.

Examples of adipic acid, azelaic acid, sebacic acid, dodecanedicarboxylic acid and terephthalic acid and / or isophthalic acid are mentioned as dicarboxylic acids.

Suitable diamines are, for example, alkanediamines having 4 to 36 carbon atoms, in particular alkanediamines having 6 to 12 carbon atoms, and aromatic diamines, for example m-xylylenediamine, di (4-aminophenyl) methane, di (4-aminocyclohexyl) methane, 2, 2-di- (4-aminophenyl) -propane, 2,2-di- (4-aminocyclohexyl) -propane or 1, 5-diamino-2-methyl-pentane.

More preferred than polyamide matrix polymers (PAM)

Polyhexamethylenadipinsäureamid, Polyhexamethylensebacinsäureamid and polycaprolactam and copolyamide 6/66 suitable, in particular with a proportion of 5 to 95 wt .-% of caprolactam units.

Also suitable as PAM are polyamides which are obtainable by copolymerization of two or more of the monomers mentioned above and below, or mixtures of several polyamides, the mixing ratio being arbitrary. Particular preference is given to mixtures of polyamide 66 with other polyamides, in particular copolyamide 6/66.

Furthermore, partially aromatic copolyamides, such as PA 6 / 6T and PA 66 / 6T, have proven to be particularly advantageous as PAMs whose triamine content is less than 0.5%, preferably less than 0.3% by weight. The production of such partly aromatic copolyamides with a low triamine content can be carried out by the processes described in EP-A 129 195 and 129 196.

The following non-exhaustive list contains the above, as well as other polyamides which are suitable as PAM, and the monomers contained.

AB polymers: PA 4 pyrrolidone

PA 6 ε-caprolactam

PA 7 ethanolactam

PA 8 capryllactam

PA 9 9-aminopelargonic acid

PA 1 1 1 1 -aminoundecanoic acid

PA 12 laurolactam

AA / BB polymers: PA 46 tetramethylenediamine, adipic acid

PA 66 hexamethylenediamine, adipic acid

PA 69 hexamethylene diamine, azelaic acid

PA 610 hexamethylenediamine, sebacic acid

PA 612 hexamethylenediamine, decanedicarboxylic acid

PA 613 hexamethylenediamine, undecanedicarboxylic acid

PA 1212 1, 12-dodecanediamine, decanedicarboxylic acid

PA 1313 1, 13-diaminotridecane, undecanedicarboxylic acid

PA 6T hexamethylenediamine, terephthalic acid

PA MXD6 m-xylyenediamine, adipic acid

PA 61 hexamethylenediamine, isophthalic acid

PA 6-3-T trimethylhexamethylenediamine, terephthalic acid

PA 6 / 6T (see PA 6 and PA 6T)

PA 6/66 (see PA 6 and PA 66)

PA 6/12 (see PA 6 and PA 12)

PA 66/6/610 (see PA 66, PA 6 and PA 610)

PA 6I / 6T (see PA 61 and PA 6T)

PA PACM 12 diaminodicyclohexylmethane, laurolactam

PA 6I / 6T / PACM such as PA 6I / 6T + diaminodicyclohexylmethane

PA 12 / MACMI laurolactam, dimethyldiaminodicyclohexylmethane, isophthalic acid

PA 12 / MACMT laurolactam, dimethyldiaminodicyclohexylmethane, terephthalic acid

PA PDA-T phenylenediamine, terephthalic acid The present invention thus also relates to a composite plastic part (CK) in which the polyamide matrix polymer (PAM) is at least one polyamide selected from the group consisting of PA 4, PA 6, PA 7, PA 8, PA 9, PA 1 1, PA 12, PA 46, PA 66, PA 69, PA 610, PA 612, PA 613, PA 1212, PA1313, PA 6T, PA MXD6, PA 61, PA 6-3-T, PA 6 / 6T, PA 6/66 , PA 6/12, PA 66/6/610, PA 6I / 6T, PA PACM 12, PA 6I / 6T / PACM, PA 12 / MACMI, PA 12 / MACMT, PA PDA-T and copolyamides of two or more of the aforementioned polyamides. Preferably, the polyamide matrix polymer (PAM) is a polyamide selected from the group consisting of PA6, PA66 and copolyamides of PA6 and PA66.

Preferably, the polyamide matrix polymer (PAM) is PA6. In another preferred embodiment, the polyamide matrix polymer (PAM) is PA66.

In another preferred embodiment, the polyamide matrix polymer (PAM) is PA6 / 66.

The PAM may further contain other conventional additives such as impact modifiers, lubricants, UV stabilizers and process stabilizers.

First fiber material (F1)

Examples of suitable materials for the first fiber material (F1) are carbon fibers, glass fibers, aramid fibers, potassium titanate fibers, boron fibers, mineral fibers (such as basalt fibers) and metallic fibers (such as steel fibers or copper fibers).

As the first fiber material (F1), an endless fiber material is preferred.

The subject matter of the present invention is thus also a method in which the first fiber material (F1) is an endless fiber material.

The terms "continuous fiber material" and "continuous fiber" are used synonymously below. In the present case, an endless fiber is understood to mean a line-shaped structure according to DIN 60 000 of practically unlimited length, which can be processed textile. An endless fiber is also called a filament. The term filament is used in textile technology. Under filament (continuous fiber) is therefore understood to be a virtually endless, fiber produced according to DI N 60 001 T 2 (December 1974) produced by chemical or technical means. In the event that an endless fiber material is used as the first fiber material (F1), continuous glass fibers are preferred. The continuous fibers can be used in the form of a knitted fabric, a knitted fabric or a fabric. It is also possible to use uni-directional continuous fibers. Such monofilament continuous fibers are also referred to as monofilaments. In the case that uni-directional continuous fibers are used, a multiplicity of endless glass fibers used in parallel are used. In this case, unidirectional layers of continuous fibers aligned parallel to one another are preferably used.

In addition, it is possible to use bi-directional or multi-directional layers of continuous fibers. In this case, the first fiber material (F1) has an elementary unidirectional layer (UD layer). Above and / or below the elemental UD layer, a further UD layer is arranged, in which the direction of the endless fibers is rotated by, for example, 90 ° to the fiber direction of the elemental UD layer. In the case of multi-directional layers, the first fiber material (F1) contains several layers (for example three, four, five or six layers) in which the directions of the fibers of the respective layers are each rotated by 90 °, for example. The angle at which the individual unidirectional layers are twisted relative to one another in the case of bi- or more-directional layers can vary within wide ranges, for example in the range of ± 10 ° to ± 90 °.

In the event that the preferred continuous fibers are used as the first fiber material (F1), the continuous fibers can each be used individually. It is also possible to individually interweave the continuous fibers or to interweave individual endless fiber bundles. The continuous fibers can also be used in the form of a fleece or a felt. Suitable continuous fiber materials are known to the person skilled in the art. Particularly preferred continuous fiber materials are glass fibers and carbon fibers. Particularly preferred are continuous glass fibers and continuous carbon fibers having a fiber diameter in the range of 9 to 34 μηη.

The matrix composition (MZ) may contain other conventional additives besides the polyamide matrix polymer (PAM) and the first fiber material (F1). Suitable additives are, for example, UV stabilizers, lubricants, nucleating agents, dyes, plasticizers. Suitable further additives are described, for example, in WO 2010/076145.

Also, the surface composition (OZ) and the second plastic component (K2) may contain other conventional additives, as described for example in WO 2010/076145. The further additives are generally present in amounts of from 0 to 5% by weight, based on the total weight of the polyamide matrix material (PAM) in the matrix composition (MZ), or based on the total weight of the polyamide surface polymer (PAO) in the surface composition (OZ ) or based on the total weight of the polyamide molding polymer (PAA) of the second plastic component (K2).

The matrix composition (MZ) generally contains from 0.01 to 5% by weight of polyethyleneimine (PEI), based on the total weight of the matrix composition (MZ).

The surface composition (OZ) and the second plastic component (K2) may also contain a polyethyleneimine (PEI). The present invention thus also relates to a composite plastic part (CK) which contains in the surface composition (OZ) in the matrix composition (MZ) and in the second plastic component (K2) a polyethyleneimine (PEI).

In another embodiment, OZ, MZ and K2 contain the same polyethylenimine (PEI).

In order to facilitate the impregnation of the first fiber material (F1) in process step ia) and to ensure complete sheathing of the fibers even at lower temperatures, it is sufficient if only the matrix composition (MZ) contains a polyethyleneimine (PEI).

The present invention thus also relates to a composite plastic part (CK) which contains a polyethyleneimine (PEI) only in the matrix composition (MZ). The matrix composition (MZ) generally contains

10 to 99.94% by weight of a polyamide matrix polymer (PAM)

0.01 to <2% by weight of a polyethyleneimine (PEI),

0.01 to 80 wt .-% of a first fiber material (F1) and

0 to 5 wt .-% of further additives, wherein the wt .-% - are each based on the total weight of MZ.

Surface Composition (OZ)

The surface composition (OZ) contains a polyamide surface polymer (PAO) and forms a surface of the first plastic component (K1). Under the In the present case, the term "a surface" is understood to mean both exactly one surface and two or more surfaces.The term "a polyamide surface polymer (PAO)" is understood here to mean both exactly one PAO and mixtures of two or more PAOs.

The surface composition (OZ) can locally form the surface of the plastic component of (K1) at a predetermined position. It is also possible that the surface composition (OZ) completely encloses the matrix composition (MZ). For the preferred case of a composite composite plastic part (CK), the surface composition (OZ) may form a surface on top of the matrix composition (MZ) and / or on the bottom of the matrix composition (MZ).

In the event that the surface composition (OZ) forms a surface only on the top side or only on the underside of the matrix composition (MZ), the surface composition (OZ) forms 10% to 50% of the total surface area of the first plastic component (K1), preferably 30 to 50% and more preferably 40 to 50% of the total surface area of the first plastic component (K1). In the event that the surface composition (OZ) forms a surface on the top side and the bottom side of the matrix composition (MZ), the surface composition (OZ) forms greater than 50% to 100% of the total surface area of the first plastic component (K1), preferably 80 to 100%. and more preferably 90 to 100% of the total surface area of the first plastic component (K1).

As the polyamide surface polymer (PAO), there can be used polyamides as described above for the polyamide matrix polymer (PAM). For the polyamide surface polymer (PAO), the above statements and preferences for the polyamide matrix polymer (PAM) thus apply accordingly.

The polyamide surface polymer (PAO) generally contains no fiber material (F1). The polyamide surface polymer (PAO) may optionally contain further additives as described above for the polyamide matrix polymer (PAM). In a preferred embodiment, the surface composition (OZ) contains no fiber material (MZ).

In a preferred embodiment, the surface composition (OZ) as the polyamide surface polymer (PAO) contains the same polyamide polymer as the polyamide matrix polymer (PAM). Thus, in a preferred embodiment, polyamide matrix polymer (PAM) and the polyamide surface polymer (PAO) are identical. However, it is also possible to use as the polyamide surface polymer (PAO) a polyamide polymer other than the polyamide matrix polymer (PAM).

In one embodiment, the surface composition (OZ) contains a polyethyleneimine (PEI).

Production of the first plastic component (KD

Process step ia) Impregnation of the first fiber material (F1)

In the event that the first fiber material (FD is an endless fiber material in the form of a mat, fleece, felt, woven fabric, knitted fabric or knitted fabric, the first fiber component (KD) is the first fiber material (FD according to method step ia ) is generally impregnated with the polyamide matrix polymer (PAM).

The various processes for producing the matrix composition (MZ) or the first plastic component (KD are known in principle to the skilled worker and, for example, in R. Stolze, Kunststoffe 78, 1988, pages 126 to 131 and in M. Wacker, GW Ehrenstein, C. Obermann , Kunststoffe 92, 2002, pages 78 to 81.

To produce the matrix composition (MZ), the first fiber material (F1) is impregnated with the polyamide matrix polymer (PAM) in method step ia). This can be done, for example, by contacting the polyamide matrix polymer (PAM) in the form of a melt with the first fiber material (F1). Another way to prepare the matrix composition (MZ) is to powder prepreg or lamination of the first fiber material (F1) with polyamide matrix polymer (PAM) films and then melt and compress the film (s) or powder applied to produce the matrix composition (MZ) ,

It is also possible to coat single filaments or filaments of filaments with the polyamide matrix polymer (PAM), subsequently to interweave the coated filaments and subsequently heat the fabric to fuse the polyamide matrix polymer (PAM) and obtain the matrix composition (MZ).

According to the invention it is crucial that the matrix composition (MZ) contains a polyethyleneimine (PEI) in order to facilitate the impregnation of the first fiber material (F1) and to ensure the complete sheathing of the fibers of the first fiber material (F1) even at lower temperatures. The polyethyleneimine (PEI) can, for example, be sprinkled onto the first fiber material (F1) as a powder. The polyethyleneimine (PEI) is preferably added to the polyamide matrix polymer (PAM). For this purpose, conventional mixing devices, such as extruders, are used. It is also possible to add the polyethylenimine (PEI) to the polyamide matrix polymer (PAM) only during the preparation of the matrix composition (MZ).

For impregnating the first fiber material (F1) according to method step ia), the polyamide matrix polymer (PAM) is generally heated in order to lower the viscosity of the polyamide matrix polymer (PAM) to such an extent that complete sheathing of the fibers of the first fiber material (F1) is ensured. In general, the polyamide matrix polymer (PAM) is compressed along with the first fiber material (F1).

The use of a polyethyleneimine (PEI) in the matrix composition (MZ) lowers the viscosity of the polyamide matrix polymer (PAM). As a result, when the polyamide matrix polymer (PAM) is heated, it is possible to reduce the viscosity already at lower temperatures compared with the prior art so that complete sheathing of the fibers of the first fiber material (F1) is ensured.

By using polyethyleneimine (PEI), a lowering (lowering) of the viscosity of the polyamide matrix polymer (PAM) is thus achieved. The zero-shear rate viscosity of the polyamide matrix polymer (PAM) is lowered by the use of polyethyleneimine (PEI) by at least 10%, preferably at least 50%, based on the viscosity of the polyamide matrix polymer (PAM) without polyethyleneimine (PEI).

The parameter used for the zero-shear rate viscosity is the viscosity number described above for the polyamide matrix polymer (PAM). The lowering of the zero-shear rate viscosity is generally in the range of 10 to 50%, preferably in the range of 20 to 40%, based on the viscosity of the polyamide matrix polymer (PAM) without polyethyleneimine (PEI). The present invention thus also relates to the composite plastic part (CK) obtainable by the process according to the invention.

The present invention therefore also provides the use of polyethyleneimine (PEI) for improving the impregnation of a first fiber material (F1) with a polyamide matrix polymer (PAM) in a process for producing a composite plastic part (CK), comprising the following steps: a) Preparation of a first plastic component (K1) comprising the following steps:

5 ia) impregnating a first fiber material (F1) with a

Polyamide matrix polymer (PAM) to obtain a matrix composition (MZ) and ib) applying a surface composition (OZ) comprising

10 polyamide surface polymer (PAO), to the matrix composition (MZ) to obtain the first plastic component (K1), the surface composition (OZ) forming a surface of the first plastic component (K1),

15 b) molding a second plastic component (K2) containing a polyamide-forming polymer (PAA) to the surface of (K1), wherein

20, the matrix composition (MZ) contains a polyethylenimine (PEI).

In general, the polyamide matrix polymer (PAM) in process step ia) to temperatures in the range of 100 to 360 ° C, preferably in the range of 150 to 310 ° C, more preferably 180 to 300 ° C and in particular in the range of 190 to 25 290th ° C, heated.

The present invention also provides a process in which the polyamide matrix polymer (PAM) in process step ia) is heated to temperatures in the range from 40 to 210 ° C.

Method step ib) application of the surface composition (OZ)

In method step ib), the surface composition (OZ) is applied to the matrix composition (MZ). As a result, the plastic component (K1) is obtained, wherein the surface composition (OZ) forms a surface of the first plastic component (K1).

The application of the surface composition (OZ) to the matrix composition can likewise be carried out by methods known to the person skilled in the art. It is possible to spread the surface composition (OZ) as a powder onto the matrix composition (MZ) and subsequently, in general under pressure to warm. Preferably, the surface composition (OZ) is laminated to the matrix composition (MZ) in the form of a film.

In general, the surface composition (OZ) in process step ib) to temperatures in the range of 100 to 360 ° C, preferably in the range of 150 to 310 ° C, more preferably 180 to 300 ° C and in particular in the range of 190 to 290 ° C, heated.

The present invention also provides a process in which the surface composition (OZ) in process step ib) is heated to temperatures in the range from 40 to 210 ° C.

In a preferred embodiment, process steps ia) and ib) are carried out simultaneously in method step a), so that the first plastic component (K1) is obtained directly.

The subject matter of the present invention is therefore also a method in which method steps ia) and ib) are carried out simultaneously in method step a).

In one embodiment, the plastic component (K1) has a layered structure. This structure is also called a sandwich structure. In the case of a sandwich structure, the plastic component (K1) has a multiplicity of layers of the first fiber material (F1). In the present case, a multiplicity is generally understood to mean 2 to 20 layers of the first fiber material (F1). Formally between each two adjacent layers of the first fiber material (F1) is at least one polymer layer in the sandwich structure. These polymer layers are formed from the polyamide matrix polymer (PAM).

For this embodiment, the general conventions and preferences with respect to K1, F1, PAM and PAO apply accordingly. In the case of a sandwich structure, this may contain 1 to 20, preferably 2 to 10 and more preferably 2 to 6 layers of the first fiber material (F1).

The production of such a sandwich structure is known per se to the person skilled in the art and can be accomplished, for example, by lamination. The production is described below using the example of a sandwich structure comprising two layers of the first fiber material (F1). For this purpose, the materials are brought together in the order listed below and then combined, preferably under pressure and heating:

A film of PAO, a layer of F1, a film of PAM, a layer of F1 and a film of PAO. The joining can be done for example under heating and pressure. For this purpose, the abovementioned materials can be supplied, for example, to a heatable roller press in which the joining takes place. By heating during assembly, the polyamide matrix polymer (PAM) used as the middle layer melts. As a result, the adjacent layers of the first fibrous material (F1) are impregnated by the polyamide matrix polymer (PAM). By means of the exemplary method described above, a sandwich structure having the following layer structure is obtained as the plastic component (K1):

PAO, F1, PAM, F1 and PAO.

Upon heating and pressing, the matrix composition (MZ) forms formally from the polyamide matrix polymer (PAM) film and the two layers from the first fiber material (F1).

The sandwich structure obtained as the first plastic component (K1) thus has formally the following layer structure: PAO, F1, PAM, F1 and PAO. F1, PAM and F1 formally form the matrix composition (MZ). The matrix composition thus consists of fiber material (F1) impregnated on both sides with the polyamide matrix polymer (PAM) in between. Depending on the degree of heating and the applied pressure, the two mats of first fiber material (F1) in the first plastic component (K1) may touch.

In the event that other additives are used, they are generally also distributed by conventional mixing devices in the respective polyamide polymer. The second plastic component (K2) may also contain a polyethyleneimine (PEI).

The matrix composition (MZ) generally contains from 0.01 to 5% by weight of a polyethyleneimine (PEI), based on the total weight of the matrix composition (MZ). The matrix composition (MZ) preferably contains 0.1 to 1% by weight of polyethylenimine (PEI), based on the total weight of the matrix composition (MZ).

The present invention thus also provides a process in which the matrix composition (MZ) contains from 0.01 to 5% by weight of polyethylenimine (PEI), based on the total weight of the matrix composition (MZ). In another embodiment, the composite plastic part (CK) generally contains from 0.01 to 5% by weight of a polyethyleneimine (PEI), based on the total weight of the composite plastic part (CK). The composite plastic part (CK) preferably contains 0.1 to 1% by weight of polyethyleneimine (PEI), based on the total weight of the composite plastic part (CK).

Polyethyleneimine (PEI)

For the purposes of the present invention, polyethyleneimines (PEI) are understood as meaning both homopolymers and copolymers which are obtainable, for example, by the processes in Ullmann (Electronic Release) under the heading "aziridines" or according to WO-A 94/12560.

The homopolymers are generally obtainable by polymerization of ethyleneimine (aziridine) in aqueous or organic solution in the presence of acid-releasing compounds, acids or Lewis acids. Such homopolymers are branched polymers, which usually contain primary, secondary and tertiary amino groups in the ratio of about 30% to 40% to 30%. The distribution of the amino groups can generally be determined by means of ¹³ C-NMR spectroscopy. This is preferably 1: 0, 8: 0.5 to 1: 1, 3: 8, in particular 1: 1, 1: 0.8 to 1: 1.

The present invention thus also provides a process in which the polyethyleneimine (PEI) contains primary, secondary and tertiary amino groups, wherein the ratio of primary to secondary to tertiary amino groups in the range of 1: 0.8: 0.5 to 1: 1, 3: 0.8.

Comonomers used are preferably compounds which have at least two amino functions. Examples of suitable comonomers are alkylenediamines having 2 to 10 C atoms in the alkylene radical, with ethylenediamine and propylenediamine being preferred. Further suitable comonomers are diethylenetriamine, triethylenetetramine, tetraethylenepentamine, dipropylenetriamine, tripropylenetriamine, diehexamethylenetriamine, aminopropylethylenediamine and bisaminopropylethylenediamine. Polyethyleneimine (PEI) usually has a weight-average molecular weight (weight average) _Mw of 600 to 3,000,000, preferably 700 to 2,000,000. The preferred M _w is from 800 to 50,000, especially from 1 100 to 25 000. The weight average molecular weight is determined by light scattering according to ASTM D4001. The present invention thus also provides a process in which the polyethyleneimine (PEI) has a weight-average molecular weight M _w in the range from 600 to 300,000 g / mol. In addition, crosslinked polyethyleneimines (PEI) which are obtainable by reaction of polyethyleneimines (PEI) with bifunctional or polyfunctional crosslinkers having as functional group at least one halohydrin, glycidyl, aziridine, isocyanate unit or a halogen atom are suitable. Examples which may be mentioned are epichlorohydrin or bichlorohydrin ethers of polyalkylene glycols having 2 to 100 ethylene oxide and / or propylene oxide units and the compounds listed in DE-A 19 93 17 20 and US Pat. No. 4,144,123. Processes for the preparation of crosslinked polyethyleneimines (PEI) are known inter alia from the abovementioned publications and EP-A 895 521 and EP-A 25 515. Furthermore, grafted polyethyleneimines (PEI) are suitable, wherein all compounds which can react with the amino or imino groups of the polyethyleneimines (PEI) can be used as the grafting agent. Suitable grafting agents and processes for the preparation of grafted polyethyleneimines (PEI) can be found, for example, in EP-A 675 914.

Likewise suitable polyethyleneimines (PEI) in the context of the invention are amidated polymers which are usually obtainable by reaction of polyethyleneimines (PEI) with carboxylic acids, their esters or anhydrides, carboxylic acid amides or carboxylic acid halides. Depending on the proportion of amidated nitrogen atoms in the Polyethyleniminkette the amidated polymers can be subsequently crosslinked with said crosslinkers. Preferably, up to 30% of the amino functions are amidated, so that sufficient primary and / or secondary nitrogen atoms are available for a subsequent crosslinking reaction. Also suitable are alkoxylated polyethyleneimines (PEI), which are obtainable, for example, by reacting polyethyleneimine (PEI) with ethylene oxide and / or propylene oxide. Such alkoxylated polymers are also crosslinkable.

Further suitable polyethyleneimines (PEI) according to the invention are hydroxyl-containing polyethyleneimines (PEI) and amphoteric polyethyleneimines (PEI) (incorporation of anionic groups) and lipophilic polyethyleneimines (PEI), which are generally obtained by incorporation of long-chain hydrocarbon radicals into the polymer chain. Methods for preparing such polyethyleneimines (PEI) are known to those skilled in the art.

As polyethyleneimines (PEI) hyperbranched polyethyleneimines (PEI) are preferred. The term "hyperbranched" in the context of the present invention means that the degree of branching (DB) of polyethyleneimine (PEI) is in the range of 10 to 99%, preferably in the range of 50 to 99%, and more preferably in the range of 60 to 99%. DB is defined as DB (%) = 100x (T + Z) / (T + Z + L), where T is the average number of terminal monomer units, Z is the mean number of branching monomer units, and L is the average number of linear bounds Monomer units in the polyethyleneimine (PEI) mean.

The present invention thus also relates to a composite plastic part (CK), which is characterized in that the polyethyleneimine (PEI) is a hyperbranched polymer with a degree of branching DB in the range from 10 to 99%, DB being defined as DB (%) = 100 x (T + Z) / (T + Z + L), where T is the average number of terminally bound monomer units, Z is the average number of branching monomer units, and L is the average number of linearly bound monomer units in the polyethyleneimine (PEI ) mean.

Second plastic component (K2)

The second plastic component (K2) contains a polyamide molding polymer (PAA). In the present case, the term "a polyamide molding polymer (PAA)" is understood to mean precisely one PAA as well as mixtures of two or more PAAs. [PA Als] As a polyamide molding polymer (PAA), it is generally possible to use the polyamides which can also be used as the polyamide matrix polymer (PAM) For the polyamide molding polymer (PAA), the comments on the polyamide matrix polymer (PAM) and the preferences given there apply accordingly.

As the polyamide molding polymer (PAA), the same polyamide as used for the polyamide matrix polymer (PAM) can be used. It is also possible to use a polyamide other than the polyamide matrix polymer (PAM) for the polyamide molding polymer (PAA).

Also, the polyamide-forming polymer (PAA) may contain other conventional additives as described above in PAO and PAM.

The polyamide-forming polymer (PAA) may also contain a polyethyleneimine (PEI). K2 may contain the same polyethylenimine (PEI) as the OZ. It is also possible that K2 contains a polyethylenimine (PEI) other than OZ. For K2 apply the Implementations and preferences for the polyethyleneimine (PEI) as made above for the surface composition (OZ) correspondingly.

The polyethyleneimine (PEI) is preferably also blended in the polyamide-forming polymer (PAA). For this purpose, known mixing devices, such as extruders, can be used. Preferably, the second plastic component (K2) also contains a fiber material for reinforcement.

The subject of the present invention is therefore also a method in which K2 contains a second fiber material (F2).

Examples of suitable materials for this second fiber material (F2) are carbon fibers, glass fibers, aramid fibers, potassium titanate fibers, boron fibers, mineral fibers (such as basalt fibers) and metallic fibers (such as steel or copper fibers).

Endless fibers are not suitable as second fiber material (F2). As second fiber material (F2), glass fibers (short glass fibers) are preferred. These glass fibers can be mixed with an extruder into a polyamide melt, for example.

The subject matter of the present invention is thus also a method in which the second fiber material (F2) is a short fiber material. The second fiber material (F2) used are preferably fibers which can be mixed into the polyamide molding polymer (PAA) by means of suitable mixing devices. The second plastic component (K2) may optionally contain further additives. As further additives, the additives mentioned above for MZ or OZ can be used.

Process step b) molding of the second plastic component (K2)

The first plastic component (K1) is generally placed in a mold. In this case, it is possible, for example, to preform the first plastic component (K1) in a preceding step in a first tool and to subsequently insert the preform thus produced into the molding tool. This is possible in particular when the first plastic component (K1) is a flat plastic element. Alternatively, it is also possible to reshape the first plastic component (K1) directly in the mold. However, it is preferred that the first plastic component (K1) preform in a first tool and subsequently insert the preform in the mold.

Furthermore, it is possible to heat the first plastic component (K1) prior to insertion into the mold or, alternatively, to heat the first plastic component (K1) in the mold. In particular, it is preferable to preheat the first plastic component (K1) and to insert the preheated first plastic component (K1) into the mold. Preferably, the mold has a temperature in the range of 40 to 210 ° C, in particular in the range of 80 to 120 ° C, on. The first plastic component (K1) is preferably heated to a temperature of 30 to 190 ° C, in particular in the range of 120 to 170 ° C prior to insertion into the mold. After inserting the first plastic component (K1), the second plastic component (K2) is introduced into the mold. Here, the second plastic component (K2) is integrally formed on the surface of the first plastic component (K1). This molding is also referred to as "overmolding." In the context of the present invention, "molding" is understood as meaning the partial molding of the second plastic component (K2) on parts of the first plastic component (K1). In addition, "molding" is understood as meaning the complete or partial encircling of the first plastic component (K1) by the second plastic component (K2). [Beim Beim] During molding, the second plastic component (K2) is formed either locally at predetermined positions on the first plastic component (K1) In addition, it is also possible to completely or partially enclose the first plastic component (K1) with the second plastic component (K2) When molding, it is also possible to form additional functional elements from the second plastic component (K2) which are attached to the plastic component Surface of the first plastic component (K1) are formed.

For molding, the second plastic component (K2), according to methods known in the art, usually melted and injected into the mold. By using the polyethyleneimine (PEI) described above, improved adhesion is achieved between the first plastic component (K1) and the second plastic component (K2) in the composite plastic part (CK). The present invention thus also provides a method in which K1 is introduced into a mold in step b) and K2 is injected into the mold for molding in the molten state. The composite plastic part (CK) produced in this way can subsequently be subjected to further processing steps. This includes, for example, further forming steps and surface treatments of the composite plastic part (CK) in order to refine its surface.

In order to achieve a good connection between the first plastic component (K1) and the second plastic component (K2), it is advantageous if the temperature at the surface of the first plastic component (K1) is above the melting temperature of the polyamide surface polymer (PAO). For this purpose, the first plastic component (K1) is usually heated. The heating of the first plastic component (K1) can be carried out as described above, directly in the mold. Alternatively, the first plastic component (K1) can also be heated outside the mold. The pressure with which the second plastic component (K2) is introduced into the mold depends on the flow direction of the melt of the second plastic component (K2). For this purpose, methods known per se for injection molding and extrusion molding are used and the pressures customary there are maintained.

Claims

claims

A method of making a composite plastic part (CK) comprising the steps of: a) preparing a first plastic component (K1) comprising the steps of: ia) impregnating a first fibrous material (F1) with a polyamide matrix polymer (PAM) to obtain a matrix composition (MZ ) and ib) applying a surface composition (OZ) containing a polyamide surface polymer (PAO) to the matrix composition (MZ) to obtain the first plastic component (K1), the surface composition (OZ) forming a surface of the first plastic component (K1), b) molding a second plastic component (K2) containing a polyamide-forming polymer (PAA) to the surface of (K1), wherein the matrix composition (MZ) contains a polyethylenimine (PEI).

A process according to claim 1, characterized in that the polyethyleneimine (PEI) has a weight-average molecular weight M _w in the range of 600 to 300,000 g / mol.

A process according to claim 1 or 2, characterized in that the polyethyleneimine (PEI) contains primary, secondary and tertiary amino groups, the ratio of primary to secondary to tertiary amino groups being in the range of 1: 0.8: 0.5 to 1: 1 , 3: 0.8.

Process according to any one of claims 1 to 3, characterized in that the polyethylenimine (PEI) is a hyperbranched polymer having a degree of branching DB in the range of 10 to 99%, DB being defined as DB (%) = 100 x (T + Z ) / (T + Z + L), where T is the average number of terminally bound monomer units, Z is the average number of branches forming monomer units and L is the average number of linearly bound monomer units in the polyethyleneimine (PEI).

A method according to any one of claims 1 to 4, characterized in that the matrix composition (MZ) contains 0.01 to 5 wt .-% polyethyleneimine (PEI), based on the total weight of the matrix composition (MZ).

Method according to one of claims 1 to 5, characterized in that the first fiber material (F1) is an endless fiber material

Method according to one of claims 1 to 6, characterized in that K2 contains a second fiber material (F2).

Method according to one of claims 1 to 7, characterized in that the second fiber material (F2) is a short fiber material.

Method according to one of claims 1 to 8, characterized in that in step b) K1 is placed in a mold and K2 is injected for molding in a molten state in the mold.

Method according to one of claims 1 to 9, characterized in that the polyamide matrix polymer (PAM) in step ia) is heated to temperatures in the range of 40 to 210 ° C.

Method according to one of claims 1 to 10, characterized in that the surface composition (OZ) in process step ib) is heated to temperatures in the range of 40 to 210 ° C.

Method according to one of claims 1 to 1 1, characterized in that in method step a), the method steps ia) and ib) are carried out simultaneously.

Method according to one of claims 1 to 12, characterized in that only the matrix composition (MZ) contains a polyethyleneimine (PEI).

Composite plastic part, obtainable according to one of claims 1 to 13.

Use of polyethyleneimine (PEI) for improving the impregnation of a first fiber material (F1) with a polyamide matrix polymer (PAM) in a process for producing a composite plastic part (CK), comprising the following steps: Preparation of a first plastic component (K1) comprising the following steps: ia) impregnating a first fiber material (F1) with a polyamide matrix polymer (PAM) to obtain a matrix composition (MZ) and ib) applying a surface composition (OZ) comprising a polyamide surface polymer (PAO) to the matrix composition (MZ) to obtain the first plastic component (K1), the surface composition (OZ) forming a surface of the first plastic component (K1),

Molding a second plastic component (K2) containing a polyamide molding polymer (PAA) to the surface of (K1), the matrix composition (MZ) containing a polyethylenimine (PEI).